A lead frame for use in the manufacture of a light-emitting device using an LED chip has been suggested (for example, Japanese Patent Application Publication No. 2006-93470; Patent Document 1).
This Patent Document 1 describes, as shown in FIG. 60, a light emitting device 100 including a heat sink 160, an LED chip 161 mounted on the heat sink 160, a pair of lead sections 330 electrically connected by bonding wires 164a, 164b to the LED chip 161 and the heat sink 160, respectively, a resin package 400 that integrally supports the heat sink 100 and the lead sections 330 and allows the LED chip 161 to be exposed on the front surface side, and an attachment lens 560 that is mounted so as to cover the front surface side of the resin package 400 through a light-transmitting resin section 550.
Further, Patent Document 1 also describes the configuration shown in FIG. 61 as the lead frame 300 that is used in the manufacture of the light emitting device 100 shown in FIG. 60. The lead frame 300 is obtained by integrally forming a pair of elongated parallel frame sections 310 that are formed parallel to each other, connection frame sections 320 that are disposed equidistantly in the longitudinal direction of the parallel frame sections 310 and connect the opposing parallel frame sections 310 to each other, a pair of lead sections 330 that extend in the directions such as to approach each other from the center portion of the mutually adjacent connection frame sections 320 and are formed such that the end portions thereof face each other at a predetermined distance from each other, and support frame sections 340 that extend from the pair of parallel frame sections 310 toward the end portions of the respective lead sections 330.
Further, an illumination fixture L has also been suggested which includes, as shown in FIG. 62A and FIG. 62B, a light source device 101, a power supply device 102 that supplies operation power to the light source device 101, and a fixture body 103 that accommodates the light source device and the power supply device (Japanese Patent Application Publication No. 2007-35890; Patent Document 2).
The light source device 101 includes a light source block BK and a case 106 accommodating the light source block BK. The light source block BK, as shown in FIG. 63, is provided with an elongated printed substrate 110 in which a wiring pattern 111 is formed on one surface side (front surface side) and a plurality of light emitting diodes 4A to 4L that are surface mounted by reflow soldering on the wiring pattern 111 of the printed substrate 110.
The light emitting diodes 4A to 4L are high-brightness white light emitting diodes of the so-called surface mounting type in which the front surface is an emission surface provided with an emission port 40 (see FIG. 64A), and the rear surface is a mounting surface where an anode terminal (not shown in the figure) and a cathode terminal (not shown in the figure) are exposed. Patent Document 2 indicates that the light emitting diodes 4A to 4L are provided substantially equidistantly in the longitudinal direction of the printed substrate 110 as shown in FIG. 64A, and used as pseudo-linear light sources.
As shown in FIG. 63A and FIG. 63B, the printed substrate 110 is a one-surface mounting substrate formed in an elongated rectangular shape. Three through holes 110a for connection to output power supply lines 107a to 107c (see FIG. 62A) of the power supply device 102 to the wiring pattern 111 are provided through the printed substrate at the left end side. Further, screw holes 110b for screwing fixing screws S1 (see FIG. 62) serving to fix the printed substrate 110 to the fixture body 103 are provided at both end portions and a center portion in the longitudinal direction of the printed substrate 110.
A paper-based copper-stretched layer plate such as a paper-based epoxy resin copper-stretched layer plate, a glass cloth-based copper-stretched layer plate such as a glass cloth-based epoxy resin copper-stretched layer plate, and a glass nonwoven fabric-based copper-stretched layer plate such as a glass nonwoven fabric-based epoxy resin copper-stretched layer plate are described as materials for the printed substrate 110.
As shown in FIG. 63A, the wiring pattern 111 to which the light emitting diodes 4A to 4L are connected is formed on the front surface side of the printed substrate 110. The wiring pattern 111 is formed using a conductive material such as a copper foil. In the printed substrate 110, a series circuit of the light emitting diodes 4A to 4F is connected in parallel in the forward direction with a series circuit of the light emitting diodes 4G to 4L.
Further, at the front surface side of the printed substrate 110, only a portion necessary for connection to the light emitting diodes 4A to 4L and the like is exposed in the wiring pattern 111, and a solder resist 112 (see FIG. 64A) for preventing the solder from adhering to the portions that are not necessary for connection is formed in the wiring pattern 111.
Meanwhile, a warping preventing section 113 is formed on the other surface side (rear surface side) of the printed substrate 110. The warping preventing section 113 is formed in a shape substantially identical to that of the wiring pattern 111 by using a copper foil, as shown in FIG. 63B. In other words, the warping preventing section 113 is a dummy wiring pattern of a shape substantially identical to that of the wiring pattern 111.
The light emitting diodes 4A to 4L are surface mounted on the printed substrate 110, and this mounting is performed by reflow soldering. When the printed substrate 110 is passed through a reflow furnace, since the thermal expansion coefficient of the wiring pattern 111 is lower than that of the printed substrate 110, thermal expansion on the front surface side of the printed substrate 110 is inhibited due to the difference in these thermal expansion coefficients, and a force causing warping toward the front surface side is generated in the printed substrate 110. However, since the warping preventing section 113 of a shape substantially identical to that of the wiring pattern 111 is formed on the rear surface side of the above-described printed substrate 110, thermal expansion is also inhibited on the rear surface side of the printed substrate 110 due to the difference in thermal expansion coefficient between the warping preventing section 113 and the printed substrate 110, and a force causing warping toward the rear surface side is generated in the printed substrate 110. As a result, thermal expansion in the printed substrate 110 is inhibited at both surfaces (front surface and rear surface). As a result, the warping caused by the difference in thermal expansion coefficient between the wiring pattern 111 and the printed substrate 110 and the warping caused by the difference in thermal expansion coefficient between the warping preventing section 113 and the printed substrate 110 are mutually compensated and eliminated, and warping of the printed substrate 110 is reduced. After the printed substrate has passed through the reflow furnace, warping is also caused by temperature variations occurring when the temperature of the printed substrate 110 drops, but warping of the printed substrate 110 is reduced for the same reasons as described hereinabove.
The case 106 where the light source block BK is accommodated is formed in an elongated box-like shape with an open lower surface by using a light-transmitting synthetic resin such as an acrylic resin. Support pieces 106a, 106a for supporting the printed substrate 110 accommodated inside the case 106 are provided integrally in a protruding condition at the lower end edges at both inner side surfaces in the longitudinal direction of the case.
The interior of the case 106 of the light source device 101 is filled with a sealing material P made of a light-transmitting resin such as a silicon resin and the resin is heated and cured in order to cause the entire case 106 to emit light and to improve heat radiation ability and waterproofing ability of the light source block BK.
Patent Document 2, as shown in FIG. 64B, indicates that a section obtained by coating the ink for silk printing so as to cover the entire surface on the rear surface side of the printed substrate 110 by silk printing (silk screen printing) can be used as an antireflection section 113. Further, Patent Document 2 also indicates that a section formed so as to cover the entire surface on the rear surface side of the printed substrate 110 by using a metal material identical to that of the wiring pattern 111 or having a thermal expansion coefficient substantially identical to that of the wiring pattern 111 may be used as the warping preventing section 113. It is also indicated that in this case, the heat radiation ability of heat-generating parts such as light emitting diodes 4A to 4L mounted on the printed substrate 110 can be increased.
A light source device configured as shown in FIG. 65 has been suggested as a surface light source using a visible light emitting diode chip (visible light LED chip) (Japanese Patent Application Publication No. H11-162233: Patent Document 3).
The light source device configured as shown in FIG. 65 includes a first visible light LED chip 103, a first translucent substrate 161 having the first visible light LED chip 103 mounted thereon, and a first translucent electrode 171 that is provided on the first translucent substrate 161 and supplies power to the first visible light LED chip 103. This light source device also includes a second visible light LED chip 104, a second translucent substrate 162 disposed opposite the mounting surface side of the first translucent substrate 161 and having the second visible light LED chip 104 mounted thereon, and a second translucent electrode 172 provided on the second translucent substrate 162 and supplying power to the second visible light LED chip 104.
In the light source device configured as shown in FIG. 65, the light from the first visible light LED chip 103 can be taken to the outside through the second translucent electrode 172 and the second translucent substrate 162, and the light from the second visible light LED chip 104 can be taken to the outside through the first translucent electrode 171 and the first translucent substrate 161.
An illuminating apparatus 600 incorporating an LED light emitting body 603 as shown in FIG. 66 has also been suggested (Japanese Patent Application Publication No. 2009-266432: Patent Document 4).
A light emitting main body 602 of the illuminating apparatus 600 is provided with a pair of attachment substrates 604, 604 and a spacer 611 that connects and fixes integrally the attachment substrates 604, 604 to each other and forms a gap 610 between the attachment substrates 604, 604. The light emitting main body 602 is also provided with plastic wiring boards 608, 608 for the LED light emitting body 603 that are attached to and integrally installed on the surfaces of the attachment substrates 604, 604, respectively, and light transmitting covers 605, 605 that are attached to the front surface side of the attachment substrates 604, 604. The attachment substrate 604 has an elongated thin band-like shape, and an extruded aluminum material is used therefor. In the wiring board 608, a plurality of LED light emitting bodies 603 are arranged with a predetermined spacing, as shown in FIG. 66 and FIG. 67.